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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/kernel/e820.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/e820.c')
-rw-r--r--arch/x86/kernel/e820.c1350
1 files changed, 1350 insertions, 0 deletions
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
new file mode 100644
index 000000000..9dac24680
--- /dev/null
+++ b/arch/x86/kernel/e820.c
@@ -0,0 +1,1350 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Low level x86 E820 memory map handling functions.
+ *
+ * The firmware and bootloader passes us the "E820 table", which is the primary
+ * physical memory layout description available about x86 systems.
+ *
+ * The kernel takes the E820 memory layout and optionally modifies it with
+ * quirks and other tweaks, and feeds that into the generic Linux memory
+ * allocation code routines via a platform independent interface (memblock, etc.).
+ */
+#include <linux/crash_dump.h>
+#include <linux/memblock.h>
+#include <linux/suspend.h>
+#include <linux/acpi.h>
+#include <linux/firmware-map.h>
+#include <linux/sort.h>
+#include <linux/memory_hotplug.h>
+
+#include <asm/e820/api.h>
+#include <asm/setup.h>
+
+/*
+ * We organize the E820 table into three main data structures:
+ *
+ * - 'e820_table_firmware': the original firmware version passed to us by the
+ * bootloader - not modified by the kernel. It is composed of two parts:
+ * the first 128 E820 memory entries in boot_params.e820_table and the remaining
+ * (if any) entries of the SETUP_E820_EXT nodes. We use this to:
+ *
+ * - inform the user about the firmware's notion of memory layout
+ * via /sys/firmware/memmap
+ *
+ * - the hibernation code uses it to generate a kernel-independent CRC32
+ * checksum of the physical memory layout of a system.
+ *
+ * - 'e820_table_kexec': a slightly modified (by the kernel) firmware version
+ * passed to us by the bootloader - the major difference between
+ * e820_table_firmware[] and this one is that, the latter marks the setup_data
+ * list created by the EFI boot stub as reserved, so that kexec can reuse the
+ * setup_data information in the second kernel. Besides, e820_table_kexec[]
+ * might also be modified by the kexec itself to fake a mptable.
+ * We use this to:
+ *
+ * - kexec, which is a bootloader in disguise, uses the original E820
+ * layout to pass to the kexec-ed kernel. This way the original kernel
+ * can have a restricted E820 map while the kexec()-ed kexec-kernel
+ * can have access to full memory - etc.
+ *
+ * - 'e820_table': this is the main E820 table that is massaged by the
+ * low level x86 platform code, or modified by boot parameters, before
+ * passed on to higher level MM layers.
+ *
+ * Once the E820 map has been converted to the standard Linux memory layout
+ * information its role stops - modifying it has no effect and does not get
+ * re-propagated. So itsmain role is a temporary bootstrap storage of firmware
+ * specific memory layout data during early bootup.
+ */
+static struct e820_table e820_table_init __initdata;
+static struct e820_table e820_table_kexec_init __initdata;
+static struct e820_table e820_table_firmware_init __initdata;
+
+struct e820_table *e820_table __refdata = &e820_table_init;
+struct e820_table *e820_table_kexec __refdata = &e820_table_kexec_init;
+struct e820_table *e820_table_firmware __refdata = &e820_table_firmware_init;
+
+/* For PCI or other memory-mapped resources */
+unsigned long pci_mem_start = 0xaeedbabe;
+#ifdef CONFIG_PCI
+EXPORT_SYMBOL(pci_mem_start);
+#endif
+
+/*
+ * This function checks if any part of the range <start,end> is mapped
+ * with type.
+ */
+static bool _e820__mapped_any(struct e820_table *table,
+ u64 start, u64 end, enum e820_type type)
+{
+ int i;
+
+ for (i = 0; i < table->nr_entries; i++) {
+ struct e820_entry *entry = &table->entries[i];
+
+ if (type && entry->type != type)
+ continue;
+ if (entry->addr >= end || entry->addr + entry->size <= start)
+ continue;
+ return true;
+ }
+ return false;
+}
+
+bool e820__mapped_raw_any(u64 start, u64 end, enum e820_type type)
+{
+ return _e820__mapped_any(e820_table_firmware, start, end, type);
+}
+EXPORT_SYMBOL_GPL(e820__mapped_raw_any);
+
+bool e820__mapped_any(u64 start, u64 end, enum e820_type type)
+{
+ return _e820__mapped_any(e820_table, start, end, type);
+}
+EXPORT_SYMBOL_GPL(e820__mapped_any);
+
+/*
+ * This function checks if the entire <start,end> range is mapped with 'type'.
+ *
+ * Note: this function only works correctly once the E820 table is sorted and
+ * not-overlapping (at least for the range specified), which is the case normally.
+ */
+static struct e820_entry *__e820__mapped_all(u64 start, u64 end,
+ enum e820_type type)
+{
+ int i;
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+
+ if (type && entry->type != type)
+ continue;
+
+ /* Is the region (part) in overlap with the current region? */
+ if (entry->addr >= end || entry->addr + entry->size <= start)
+ continue;
+
+ /*
+ * If the region is at the beginning of <start,end> we move
+ * 'start' to the end of the region since it's ok until there
+ */
+ if (entry->addr <= start)
+ start = entry->addr + entry->size;
+
+ /*
+ * If 'start' is now at or beyond 'end', we're done, full
+ * coverage of the desired range exists:
+ */
+ if (start >= end)
+ return entry;
+ }
+
+ return NULL;
+}
+
+/*
+ * This function checks if the entire range <start,end> is mapped with type.
+ */
+bool __init e820__mapped_all(u64 start, u64 end, enum e820_type type)
+{
+ return __e820__mapped_all(start, end, type);
+}
+
+/*
+ * This function returns the type associated with the range <start,end>.
+ */
+int e820__get_entry_type(u64 start, u64 end)
+{
+ struct e820_entry *entry = __e820__mapped_all(start, end, 0);
+
+ return entry ? entry->type : -EINVAL;
+}
+
+/*
+ * Add a memory region to the kernel E820 map.
+ */
+static void __init __e820__range_add(struct e820_table *table, u64 start, u64 size, enum e820_type type)
+{
+ int x = table->nr_entries;
+
+ if (x >= ARRAY_SIZE(table->entries)) {
+ pr_err("too many entries; ignoring [mem %#010llx-%#010llx]\n",
+ start, start + size - 1);
+ return;
+ }
+
+ table->entries[x].addr = start;
+ table->entries[x].size = size;
+ table->entries[x].type = type;
+ table->nr_entries++;
+}
+
+void __init e820__range_add(u64 start, u64 size, enum e820_type type)
+{
+ __e820__range_add(e820_table, start, size, type);
+}
+
+static void __init e820_print_type(enum e820_type type)
+{
+ switch (type) {
+ case E820_TYPE_RAM: /* Fall through: */
+ case E820_TYPE_RESERVED_KERN: pr_cont("usable"); break;
+ case E820_TYPE_RESERVED: pr_cont("reserved"); break;
+ case E820_TYPE_SOFT_RESERVED: pr_cont("soft reserved"); break;
+ case E820_TYPE_ACPI: pr_cont("ACPI data"); break;
+ case E820_TYPE_NVS: pr_cont("ACPI NVS"); break;
+ case E820_TYPE_UNUSABLE: pr_cont("unusable"); break;
+ case E820_TYPE_PMEM: /* Fall through: */
+ case E820_TYPE_PRAM: pr_cont("persistent (type %u)", type); break;
+ default: pr_cont("type %u", type); break;
+ }
+}
+
+void __init e820__print_table(char *who)
+{
+ int i;
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ pr_info("%s: [mem %#018Lx-%#018Lx] ",
+ who,
+ e820_table->entries[i].addr,
+ e820_table->entries[i].addr + e820_table->entries[i].size - 1);
+
+ e820_print_type(e820_table->entries[i].type);
+ pr_cont("\n");
+ }
+}
+
+/*
+ * Sanitize an E820 map.
+ *
+ * Some E820 layouts include overlapping entries. The following
+ * replaces the original E820 map with a new one, removing overlaps,
+ * and resolving conflicting memory types in favor of highest
+ * numbered type.
+ *
+ * The input parameter 'entries' points to an array of 'struct
+ * e820_entry' which on entry has elements in the range [0, *nr_entries)
+ * valid, and which has space for up to max_nr_entries entries.
+ * On return, the resulting sanitized E820 map entries will be in
+ * overwritten in the same location, starting at 'entries'.
+ *
+ * The integer pointed to by nr_entries must be valid on entry (the
+ * current number of valid entries located at 'entries'). If the
+ * sanitizing succeeds the *nr_entries will be updated with the new
+ * number of valid entries (something no more than max_nr_entries).
+ *
+ * The return value from e820__update_table() is zero if it
+ * successfully 'sanitized' the map entries passed in, and is -1
+ * if it did nothing, which can happen if either of (1) it was
+ * only passed one map entry, or (2) any of the input map entries
+ * were invalid (start + size < start, meaning that the size was
+ * so big the described memory range wrapped around through zero.)
+ *
+ * Visually we're performing the following
+ * (1,2,3,4 = memory types)...
+ *
+ * Sample memory map (w/overlaps):
+ * ____22__________________
+ * ______________________4_
+ * ____1111________________
+ * _44_____________________
+ * 11111111________________
+ * ____________________33__
+ * ___________44___________
+ * __________33333_________
+ * ______________22________
+ * ___________________2222_
+ * _________111111111______
+ * _____________________11_
+ * _________________4______
+ *
+ * Sanitized equivalent (no overlap):
+ * 1_______________________
+ * _44_____________________
+ * ___1____________________
+ * ____22__________________
+ * ______11________________
+ * _________1______________
+ * __________3_____________
+ * ___________44___________
+ * _____________33_________
+ * _______________2________
+ * ________________1_______
+ * _________________4______
+ * ___________________2____
+ * ____________________33__
+ * ______________________4_
+ */
+struct change_member {
+ /* Pointer to the original entry: */
+ struct e820_entry *entry;
+ /* Address for this change point: */
+ unsigned long long addr;
+};
+
+static struct change_member change_point_list[2*E820_MAX_ENTRIES] __initdata;
+static struct change_member *change_point[2*E820_MAX_ENTRIES] __initdata;
+static struct e820_entry *overlap_list[E820_MAX_ENTRIES] __initdata;
+static struct e820_entry new_entries[E820_MAX_ENTRIES] __initdata;
+
+static int __init cpcompare(const void *a, const void *b)
+{
+ struct change_member * const *app = a, * const *bpp = b;
+ const struct change_member *ap = *app, *bp = *bpp;
+
+ /*
+ * Inputs are pointers to two elements of change_point[]. If their
+ * addresses are not equal, their difference dominates. If the addresses
+ * are equal, then consider one that represents the end of its region
+ * to be greater than one that does not.
+ */
+ if (ap->addr != bp->addr)
+ return ap->addr > bp->addr ? 1 : -1;
+
+ return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr);
+}
+
+static bool e820_nomerge(enum e820_type type)
+{
+ /*
+ * These types may indicate distinct platform ranges aligned to
+ * numa node, protection domain, performance domain, or other
+ * boundaries. Do not merge them.
+ */
+ if (type == E820_TYPE_PRAM)
+ return true;
+ if (type == E820_TYPE_SOFT_RESERVED)
+ return true;
+ return false;
+}
+
+int __init e820__update_table(struct e820_table *table)
+{
+ struct e820_entry *entries = table->entries;
+ u32 max_nr_entries = ARRAY_SIZE(table->entries);
+ enum e820_type current_type, last_type;
+ unsigned long long last_addr;
+ u32 new_nr_entries, overlap_entries;
+ u32 i, chg_idx, chg_nr;
+
+ /* If there's only one memory region, don't bother: */
+ if (table->nr_entries < 2)
+ return -1;
+
+ BUG_ON(table->nr_entries > max_nr_entries);
+
+ /* Bail out if we find any unreasonable addresses in the map: */
+ for (i = 0; i < table->nr_entries; i++) {
+ if (entries[i].addr + entries[i].size < entries[i].addr)
+ return -1;
+ }
+
+ /* Create pointers for initial change-point information (for sorting): */
+ for (i = 0; i < 2 * table->nr_entries; i++)
+ change_point[i] = &change_point_list[i];
+
+ /*
+ * Record all known change-points (starting and ending addresses),
+ * omitting empty memory regions:
+ */
+ chg_idx = 0;
+ for (i = 0; i < table->nr_entries; i++) {
+ if (entries[i].size != 0) {
+ change_point[chg_idx]->addr = entries[i].addr;
+ change_point[chg_idx++]->entry = &entries[i];
+ change_point[chg_idx]->addr = entries[i].addr + entries[i].size;
+ change_point[chg_idx++]->entry = &entries[i];
+ }
+ }
+ chg_nr = chg_idx;
+
+ /* Sort change-point list by memory addresses (low -> high): */
+ sort(change_point, chg_nr, sizeof(*change_point), cpcompare, NULL);
+
+ /* Create a new memory map, removing overlaps: */
+ overlap_entries = 0; /* Number of entries in the overlap table */
+ new_nr_entries = 0; /* Index for creating new map entries */
+ last_type = 0; /* Start with undefined memory type */
+ last_addr = 0; /* Start with 0 as last starting address */
+
+ /* Loop through change-points, determining effect on the new map: */
+ for (chg_idx = 0; chg_idx < chg_nr; chg_idx++) {
+ /* Keep track of all overlapping entries */
+ if (change_point[chg_idx]->addr == change_point[chg_idx]->entry->addr) {
+ /* Add map entry to overlap list (> 1 entry implies an overlap) */
+ overlap_list[overlap_entries++] = change_point[chg_idx]->entry;
+ } else {
+ /* Remove entry from list (order independent, so swap with last): */
+ for (i = 0; i < overlap_entries; i++) {
+ if (overlap_list[i] == change_point[chg_idx]->entry)
+ overlap_list[i] = overlap_list[overlap_entries-1];
+ }
+ overlap_entries--;
+ }
+ /*
+ * If there are overlapping entries, decide which
+ * "type" to use (larger value takes precedence --
+ * 1=usable, 2,3,4,4+=unusable)
+ */
+ current_type = 0;
+ for (i = 0; i < overlap_entries; i++) {
+ if (overlap_list[i]->type > current_type)
+ current_type = overlap_list[i]->type;
+ }
+
+ /* Continue building up new map based on this information: */
+ if (current_type != last_type || e820_nomerge(current_type)) {
+ if (last_type != 0) {
+ new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr;
+ /* Move forward only if the new size was non-zero: */
+ if (new_entries[new_nr_entries].size != 0)
+ /* No more space left for new entries? */
+ if (++new_nr_entries >= max_nr_entries)
+ break;
+ }
+ if (current_type != 0) {
+ new_entries[new_nr_entries].addr = change_point[chg_idx]->addr;
+ new_entries[new_nr_entries].type = current_type;
+ last_addr = change_point[chg_idx]->addr;
+ }
+ last_type = current_type;
+ }
+ }
+
+ /* Copy the new entries into the original location: */
+ memcpy(entries, new_entries, new_nr_entries*sizeof(*entries));
+ table->nr_entries = new_nr_entries;
+
+ return 0;
+}
+
+static int __init __append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)
+{
+ struct boot_e820_entry *entry = entries;
+
+ while (nr_entries) {
+ u64 start = entry->addr;
+ u64 size = entry->size;
+ u64 end = start + size - 1;
+ u32 type = entry->type;
+
+ /* Ignore the entry on 64-bit overflow: */
+ if (start > end && likely(size))
+ return -1;
+
+ e820__range_add(start, size, type);
+
+ entry++;
+ nr_entries--;
+ }
+ return 0;
+}
+
+/*
+ * Copy the BIOS E820 map into a safe place.
+ *
+ * Sanity-check it while we're at it..
+ *
+ * If we're lucky and live on a modern system, the setup code
+ * will have given us a memory map that we can use to properly
+ * set up memory. If we aren't, we'll fake a memory map.
+ */
+static int __init append_e820_table(struct boot_e820_entry *entries, u32 nr_entries)
+{
+ /* Only one memory region (or negative)? Ignore it */
+ if (nr_entries < 2)
+ return -1;
+
+ return __append_e820_table(entries, nr_entries);
+}
+
+static u64 __init
+__e820__range_update(struct e820_table *table, u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
+{
+ u64 end;
+ unsigned int i;
+ u64 real_updated_size = 0;
+
+ BUG_ON(old_type == new_type);
+
+ if (size > (ULLONG_MAX - start))
+ size = ULLONG_MAX - start;
+
+ end = start + size;
+ printk(KERN_DEBUG "e820: update [mem %#010Lx-%#010Lx] ", start, end - 1);
+ e820_print_type(old_type);
+ pr_cont(" ==> ");
+ e820_print_type(new_type);
+ pr_cont("\n");
+
+ for (i = 0; i < table->nr_entries; i++) {
+ struct e820_entry *entry = &table->entries[i];
+ u64 final_start, final_end;
+ u64 entry_end;
+
+ if (entry->type != old_type)
+ continue;
+
+ entry_end = entry->addr + entry->size;
+
+ /* Completely covered by new range? */
+ if (entry->addr >= start && entry_end <= end) {
+ entry->type = new_type;
+ real_updated_size += entry->size;
+ continue;
+ }
+
+ /* New range is completely covered? */
+ if (entry->addr < start && entry_end > end) {
+ __e820__range_add(table, start, size, new_type);
+ __e820__range_add(table, end, entry_end - end, entry->type);
+ entry->size = start - entry->addr;
+ real_updated_size += size;
+ continue;
+ }
+
+ /* Partially covered: */
+ final_start = max(start, entry->addr);
+ final_end = min(end, entry_end);
+ if (final_start >= final_end)
+ continue;
+
+ __e820__range_add(table, final_start, final_end - final_start, new_type);
+
+ real_updated_size += final_end - final_start;
+
+ /*
+ * Left range could be head or tail, so need to update
+ * its size first:
+ */
+ entry->size -= final_end - final_start;
+ if (entry->addr < final_start)
+ continue;
+
+ entry->addr = final_end;
+ }
+ return real_updated_size;
+}
+
+u64 __init e820__range_update(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
+{
+ return __e820__range_update(e820_table, start, size, old_type, new_type);
+}
+
+static u64 __init e820__range_update_kexec(u64 start, u64 size, enum e820_type old_type, enum e820_type new_type)
+{
+ return __e820__range_update(e820_table_kexec, start, size, old_type, new_type);
+}
+
+/* Remove a range of memory from the E820 table: */
+u64 __init e820__range_remove(u64 start, u64 size, enum e820_type old_type, bool check_type)
+{
+ int i;
+ u64 end;
+ u64 real_removed_size = 0;
+
+ if (size > (ULLONG_MAX - start))
+ size = ULLONG_MAX - start;
+
+ end = start + size;
+ printk(KERN_DEBUG "e820: remove [mem %#010Lx-%#010Lx] ", start, end - 1);
+ if (check_type)
+ e820_print_type(old_type);
+ pr_cont("\n");
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+ u64 final_start, final_end;
+ u64 entry_end;
+
+ if (check_type && entry->type != old_type)
+ continue;
+
+ entry_end = entry->addr + entry->size;
+
+ /* Completely covered? */
+ if (entry->addr >= start && entry_end <= end) {
+ real_removed_size += entry->size;
+ memset(entry, 0, sizeof(*entry));
+ continue;
+ }
+
+ /* Is the new range completely covered? */
+ if (entry->addr < start && entry_end > end) {
+ e820__range_add(end, entry_end - end, entry->type);
+ entry->size = start - entry->addr;
+ real_removed_size += size;
+ continue;
+ }
+
+ /* Partially covered: */
+ final_start = max(start, entry->addr);
+ final_end = min(end, entry_end);
+ if (final_start >= final_end)
+ continue;
+
+ real_removed_size += final_end - final_start;
+
+ /*
+ * Left range could be head or tail, so need to update
+ * the size first:
+ */
+ entry->size -= final_end - final_start;
+ if (entry->addr < final_start)
+ continue;
+
+ entry->addr = final_end;
+ }
+ return real_removed_size;
+}
+
+void __init e820__update_table_print(void)
+{
+ if (e820__update_table(e820_table))
+ return;
+
+ pr_info("modified physical RAM map:\n");
+ e820__print_table("modified");
+}
+
+static void __init e820__update_table_kexec(void)
+{
+ e820__update_table(e820_table_kexec);
+}
+
+#define MAX_GAP_END 0x100000000ull
+
+/*
+ * Search for a gap in the E820 memory space from 0 to MAX_GAP_END (4GB).
+ */
+static int __init e820_search_gap(unsigned long *gapstart, unsigned long *gapsize)
+{
+ unsigned long long last = MAX_GAP_END;
+ int i = e820_table->nr_entries;
+ int found = 0;
+
+ while (--i >= 0) {
+ unsigned long long start = e820_table->entries[i].addr;
+ unsigned long long end = start + e820_table->entries[i].size;
+
+ /*
+ * Since "last" is at most 4GB, we know we'll
+ * fit in 32 bits if this condition is true:
+ */
+ if (last > end) {
+ unsigned long gap = last - end;
+
+ if (gap >= *gapsize) {
+ *gapsize = gap;
+ *gapstart = end;
+ found = 1;
+ }
+ }
+ if (start < last)
+ last = start;
+ }
+ return found;
+}
+
+/*
+ * Search for the biggest gap in the low 32 bits of the E820
+ * memory space. We pass this space to the PCI subsystem, so
+ * that it can assign MMIO resources for hotplug or
+ * unconfigured devices in.
+ *
+ * Hopefully the BIOS let enough space left.
+ */
+__init void e820__setup_pci_gap(void)
+{
+ unsigned long gapstart, gapsize;
+ int found;
+
+ gapsize = 0x400000;
+ found = e820_search_gap(&gapstart, &gapsize);
+
+ if (!found) {
+#ifdef CONFIG_X86_64
+ gapstart = (max_pfn << PAGE_SHIFT) + 1024*1024;
+ pr_err("Cannot find an available gap in the 32-bit address range\n");
+ pr_err("PCI devices with unassigned 32-bit BARs may not work!\n");
+#else
+ gapstart = 0x10000000;
+#endif
+ }
+
+ /*
+ * e820__reserve_resources_late() protects stolen RAM already:
+ */
+ pci_mem_start = gapstart;
+
+ pr_info("[mem %#010lx-%#010lx] available for PCI devices\n",
+ gapstart, gapstart + gapsize - 1);
+}
+
+/*
+ * Called late during init, in free_initmem().
+ *
+ * Initial e820_table and e820_table_kexec are largish __initdata arrays.
+ *
+ * Copy them to a (usually much smaller) dynamically allocated area that is
+ * sized precisely after the number of e820 entries.
+ *
+ * This is done after we've performed all the fixes and tweaks to the tables.
+ * All functions which modify them are __init functions, which won't exist
+ * after free_initmem().
+ */
+__init void e820__reallocate_tables(void)
+{
+ struct e820_table *n;
+ int size;
+
+ size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table->nr_entries;
+ n = kmemdup(e820_table, size, GFP_KERNEL);
+ BUG_ON(!n);
+ e820_table = n;
+
+ size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_kexec->nr_entries;
+ n = kmemdup(e820_table_kexec, size, GFP_KERNEL);
+ BUG_ON(!n);
+ e820_table_kexec = n;
+
+ size = offsetof(struct e820_table, entries) + sizeof(struct e820_entry)*e820_table_firmware->nr_entries;
+ n = kmemdup(e820_table_firmware, size, GFP_KERNEL);
+ BUG_ON(!n);
+ e820_table_firmware = n;
+}
+
+/*
+ * Because of the small fixed size of struct boot_params, only the first
+ * 128 E820 memory entries are passed to the kernel via boot_params.e820_table,
+ * the remaining (if any) entries are passed via the SETUP_E820_EXT node of
+ * struct setup_data, which is parsed here.
+ */
+void __init e820__memory_setup_extended(u64 phys_addr, u32 data_len)
+{
+ int entries;
+ struct boot_e820_entry *extmap;
+ struct setup_data *sdata;
+
+ sdata = early_memremap(phys_addr, data_len);
+ entries = sdata->len / sizeof(*extmap);
+ extmap = (struct boot_e820_entry *)(sdata->data);
+
+ __append_e820_table(extmap, entries);
+ e820__update_table(e820_table);
+
+ memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
+ memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
+
+ early_memunmap(sdata, data_len);
+ pr_info("extended physical RAM map:\n");
+ e820__print_table("extended");
+}
+
+/*
+ * Find the ranges of physical addresses that do not correspond to
+ * E820 RAM areas and register the corresponding pages as 'nosave' for
+ * hibernation (32-bit) or software suspend and suspend to RAM (64-bit).
+ *
+ * This function requires the E820 map to be sorted and without any
+ * overlapping entries.
+ */
+void __init e820__register_nosave_regions(unsigned long limit_pfn)
+{
+ int i;
+ unsigned long pfn = 0;
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+
+ if (pfn < PFN_UP(entry->addr))
+ register_nosave_region(pfn, PFN_UP(entry->addr));
+
+ pfn = PFN_DOWN(entry->addr + entry->size);
+
+ if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
+ register_nosave_region(PFN_UP(entry->addr), pfn);
+
+ if (pfn >= limit_pfn)
+ break;
+ }
+}
+
+#ifdef CONFIG_ACPI
+/*
+ * Register ACPI NVS memory regions, so that we can save/restore them during
+ * hibernation and the subsequent resume:
+ */
+static int __init e820__register_nvs_regions(void)
+{
+ int i;
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+
+ if (entry->type == E820_TYPE_NVS)
+ acpi_nvs_register(entry->addr, entry->size);
+ }
+
+ return 0;
+}
+core_initcall(e820__register_nvs_regions);
+#endif
+
+/*
+ * Allocate the requested number of bytes with the requested alignment
+ * and return (the physical address) to the caller. Also register this
+ * range in the 'kexec' E820 table as a reserved range.
+ *
+ * This allows kexec to fake a new mptable, as if it came from the real
+ * system.
+ */
+u64 __init e820__memblock_alloc_reserved(u64 size, u64 align)
+{
+ u64 addr;
+
+ addr = memblock_phys_alloc(size, align);
+ if (addr) {
+ e820__range_update_kexec(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
+ pr_info("update e820_table_kexec for e820__memblock_alloc_reserved()\n");
+ e820__update_table_kexec();
+ }
+
+ return addr;
+}
+
+#ifdef CONFIG_X86_32
+# ifdef CONFIG_X86_PAE
+# define MAX_ARCH_PFN (1ULL<<(36-PAGE_SHIFT))
+# else
+# define MAX_ARCH_PFN (1ULL<<(32-PAGE_SHIFT))
+# endif
+#else /* CONFIG_X86_32 */
+# define MAX_ARCH_PFN MAXMEM>>PAGE_SHIFT
+#endif
+
+/*
+ * Find the highest page frame number we have available
+ */
+static unsigned long __init e820_end_pfn(unsigned long limit_pfn, enum e820_type type)
+{
+ int i;
+ unsigned long last_pfn = 0;
+ unsigned long max_arch_pfn = MAX_ARCH_PFN;
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+ unsigned long start_pfn;
+ unsigned long end_pfn;
+
+ if (entry->type != type)
+ continue;
+
+ start_pfn = entry->addr >> PAGE_SHIFT;
+ end_pfn = (entry->addr + entry->size) >> PAGE_SHIFT;
+
+ if (start_pfn >= limit_pfn)
+ continue;
+ if (end_pfn > limit_pfn) {
+ last_pfn = limit_pfn;
+ break;
+ }
+ if (end_pfn > last_pfn)
+ last_pfn = end_pfn;
+ }
+
+ if (last_pfn > max_arch_pfn)
+ last_pfn = max_arch_pfn;
+
+ pr_info("last_pfn = %#lx max_arch_pfn = %#lx\n",
+ last_pfn, max_arch_pfn);
+ return last_pfn;
+}
+
+unsigned long __init e820__end_of_ram_pfn(void)
+{
+ return e820_end_pfn(MAX_ARCH_PFN, E820_TYPE_RAM);
+}
+
+unsigned long __init e820__end_of_low_ram_pfn(void)
+{
+ return e820_end_pfn(1UL << (32 - PAGE_SHIFT), E820_TYPE_RAM);
+}
+
+static void __init early_panic(char *msg)
+{
+ early_printk(msg);
+ panic(msg);
+}
+
+static int userdef __initdata;
+
+/* The "mem=nopentium" boot option disables 4MB page tables on 32-bit kernels: */
+static int __init parse_memopt(char *p)
+{
+ u64 mem_size;
+
+ if (!p)
+ return -EINVAL;
+
+ if (!strcmp(p, "nopentium")) {
+#ifdef CONFIG_X86_32
+ setup_clear_cpu_cap(X86_FEATURE_PSE);
+ return 0;
+#else
+ pr_warn("mem=nopentium ignored! (only supported on x86_32)\n");
+ return -EINVAL;
+#endif
+ }
+
+ userdef = 1;
+ mem_size = memparse(p, &p);
+
+ /* Don't remove all memory when getting "mem={invalid}" parameter: */
+ if (mem_size == 0)
+ return -EINVAL;
+
+ e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+ max_mem_size = mem_size;
+#endif
+
+ return 0;
+}
+early_param("mem", parse_memopt);
+
+static int __init parse_memmap_one(char *p)
+{
+ char *oldp;
+ u64 start_at, mem_size;
+
+ if (!p)
+ return -EINVAL;
+
+ if (!strncmp(p, "exactmap", 8)) {
+ e820_table->nr_entries = 0;
+ userdef = 1;
+ return 0;
+ }
+
+ oldp = p;
+ mem_size = memparse(p, &p);
+ if (p == oldp)
+ return -EINVAL;
+
+ userdef = 1;
+ if (*p == '@') {
+ start_at = memparse(p+1, &p);
+ e820__range_add(start_at, mem_size, E820_TYPE_RAM);
+ } else if (*p == '#') {
+ start_at = memparse(p+1, &p);
+ e820__range_add(start_at, mem_size, E820_TYPE_ACPI);
+ } else if (*p == '$') {
+ start_at = memparse(p+1, &p);
+ e820__range_add(start_at, mem_size, E820_TYPE_RESERVED);
+ } else if (*p == '!') {
+ start_at = memparse(p+1, &p);
+ e820__range_add(start_at, mem_size, E820_TYPE_PRAM);
+ } else if (*p == '%') {
+ enum e820_type from = 0, to = 0;
+
+ start_at = memparse(p + 1, &p);
+ if (*p == '-')
+ from = simple_strtoull(p + 1, &p, 0);
+ if (*p == '+')
+ to = simple_strtoull(p + 1, &p, 0);
+ if (*p != '\0')
+ return -EINVAL;
+ if (from && to)
+ e820__range_update(start_at, mem_size, from, to);
+ else if (to)
+ e820__range_add(start_at, mem_size, to);
+ else if (from)
+ e820__range_remove(start_at, mem_size, from, 1);
+ else
+ e820__range_remove(start_at, mem_size, 0, 0);
+ } else {
+ e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
+ }
+
+ return *p == '\0' ? 0 : -EINVAL;
+}
+
+static int __init parse_memmap_opt(char *str)
+{
+ while (str) {
+ char *k = strchr(str, ',');
+
+ if (k)
+ *k++ = 0;
+
+ parse_memmap_one(str);
+ str = k;
+ }
+
+ return 0;
+}
+early_param("memmap", parse_memmap_opt);
+
+/*
+ * Reserve all entries from the bootloader's extensible data nodes list,
+ * because if present we are going to use it later on to fetch e820
+ * entries from it:
+ */
+void __init e820__reserve_setup_data(void)
+{
+ struct setup_indirect *indirect;
+ struct setup_data *data;
+ u64 pa_data, pa_next;
+ u32 len;
+
+ pa_data = boot_params.hdr.setup_data;
+ if (!pa_data)
+ return;
+
+ while (pa_data) {
+ data = early_memremap(pa_data, sizeof(*data));
+ if (!data) {
+ pr_warn("e820: failed to memremap setup_data entry\n");
+ return;
+ }
+
+ len = sizeof(*data);
+ pa_next = data->next;
+
+ e820__range_update(pa_data, sizeof(*data)+data->len, E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
+
+ /*
+ * SETUP_EFI and SETUP_IMA are supplied by kexec and do not need
+ * to be reserved.
+ */
+ if (data->type != SETUP_EFI && data->type != SETUP_IMA)
+ e820__range_update_kexec(pa_data,
+ sizeof(*data) + data->len,
+ E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
+
+ if (data->type == SETUP_INDIRECT) {
+ len += data->len;
+ early_memunmap(data, sizeof(*data));
+ data = early_memremap(pa_data, len);
+ if (!data) {
+ pr_warn("e820: failed to memremap indirect setup_data\n");
+ return;
+ }
+
+ indirect = (struct setup_indirect *)data->data;
+
+ if (indirect->type != SETUP_INDIRECT) {
+ e820__range_update(indirect->addr, indirect->len,
+ E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
+ e820__range_update_kexec(indirect->addr, indirect->len,
+ E820_TYPE_RAM, E820_TYPE_RESERVED_KERN);
+ }
+ }
+
+ pa_data = pa_next;
+ early_memunmap(data, len);
+ }
+
+ e820__update_table(e820_table);
+ e820__update_table(e820_table_kexec);
+
+ pr_info("extended physical RAM map:\n");
+ e820__print_table("reserve setup_data");
+}
+
+/*
+ * Called after parse_early_param(), after early parameters (such as mem=)
+ * have been processed, in which case we already have an E820 table filled in
+ * via the parameter callback function(s), but it's not sorted and printed yet:
+ */
+void __init e820__finish_early_params(void)
+{
+ if (userdef) {
+ if (e820__update_table(e820_table) < 0)
+ early_panic("Invalid user supplied memory map");
+
+ pr_info("user-defined physical RAM map:\n");
+ e820__print_table("user");
+ }
+}
+
+static const char *__init e820_type_to_string(struct e820_entry *entry)
+{
+ switch (entry->type) {
+ case E820_TYPE_RESERVED_KERN: /* Fall-through: */
+ case E820_TYPE_RAM: return "System RAM";
+ case E820_TYPE_ACPI: return "ACPI Tables";
+ case E820_TYPE_NVS: return "ACPI Non-volatile Storage";
+ case E820_TYPE_UNUSABLE: return "Unusable memory";
+ case E820_TYPE_PRAM: return "Persistent Memory (legacy)";
+ case E820_TYPE_PMEM: return "Persistent Memory";
+ case E820_TYPE_RESERVED: return "Reserved";
+ case E820_TYPE_SOFT_RESERVED: return "Soft Reserved";
+ default: return "Unknown E820 type";
+ }
+}
+
+static unsigned long __init e820_type_to_iomem_type(struct e820_entry *entry)
+{
+ switch (entry->type) {
+ case E820_TYPE_RESERVED_KERN: /* Fall-through: */
+ case E820_TYPE_RAM: return IORESOURCE_SYSTEM_RAM;
+ case E820_TYPE_ACPI: /* Fall-through: */
+ case E820_TYPE_NVS: /* Fall-through: */
+ case E820_TYPE_UNUSABLE: /* Fall-through: */
+ case E820_TYPE_PRAM: /* Fall-through: */
+ case E820_TYPE_PMEM: /* Fall-through: */
+ case E820_TYPE_RESERVED: /* Fall-through: */
+ case E820_TYPE_SOFT_RESERVED: /* Fall-through: */
+ default: return IORESOURCE_MEM;
+ }
+}
+
+static unsigned long __init e820_type_to_iores_desc(struct e820_entry *entry)
+{
+ switch (entry->type) {
+ case E820_TYPE_ACPI: return IORES_DESC_ACPI_TABLES;
+ case E820_TYPE_NVS: return IORES_DESC_ACPI_NV_STORAGE;
+ case E820_TYPE_PMEM: return IORES_DESC_PERSISTENT_MEMORY;
+ case E820_TYPE_PRAM: return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
+ case E820_TYPE_RESERVED: return IORES_DESC_RESERVED;
+ case E820_TYPE_SOFT_RESERVED: return IORES_DESC_SOFT_RESERVED;
+ case E820_TYPE_RESERVED_KERN: /* Fall-through: */
+ case E820_TYPE_RAM: /* Fall-through: */
+ case E820_TYPE_UNUSABLE: /* Fall-through: */
+ default: return IORES_DESC_NONE;
+ }
+}
+
+static bool __init do_mark_busy(enum e820_type type, struct resource *res)
+{
+ /* this is the legacy bios/dos rom-shadow + mmio region */
+ if (res->start < (1ULL<<20))
+ return true;
+
+ /*
+ * Treat persistent memory and other special memory ranges like
+ * device memory, i.e. reserve it for exclusive use of a driver
+ */
+ switch (type) {
+ case E820_TYPE_RESERVED:
+ case E820_TYPE_SOFT_RESERVED:
+ case E820_TYPE_PRAM:
+ case E820_TYPE_PMEM:
+ return false;
+ case E820_TYPE_RESERVED_KERN:
+ case E820_TYPE_RAM:
+ case E820_TYPE_ACPI:
+ case E820_TYPE_NVS:
+ case E820_TYPE_UNUSABLE:
+ default:
+ return true;
+ }
+}
+
+/*
+ * Mark E820 reserved areas as busy for the resource manager:
+ */
+
+static struct resource __initdata *e820_res;
+
+void __init e820__reserve_resources(void)
+{
+ int i;
+ struct resource *res;
+ u64 end;
+
+ res = memblock_alloc(sizeof(*res) * e820_table->nr_entries,
+ SMP_CACHE_BYTES);
+ if (!res)
+ panic("%s: Failed to allocate %zu bytes\n", __func__,
+ sizeof(*res) * e820_table->nr_entries);
+ e820_res = res;
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = e820_table->entries + i;
+
+ end = entry->addr + entry->size - 1;
+ if (end != (resource_size_t)end) {
+ res++;
+ continue;
+ }
+ res->start = entry->addr;
+ res->end = end;
+ res->name = e820_type_to_string(entry);
+ res->flags = e820_type_to_iomem_type(entry);
+ res->desc = e820_type_to_iores_desc(entry);
+
+ /*
+ * Don't register the region that could be conflicted with
+ * PCI device BAR resources and insert them later in
+ * pcibios_resource_survey():
+ */
+ if (do_mark_busy(entry->type, res)) {
+ res->flags |= IORESOURCE_BUSY;
+ insert_resource(&iomem_resource, res);
+ }
+ res++;
+ }
+
+ /* Expose the bootloader-provided memory layout to the sysfs. */
+ for (i = 0; i < e820_table_firmware->nr_entries; i++) {
+ struct e820_entry *entry = e820_table_firmware->entries + i;
+
+ firmware_map_add_early(entry->addr, entry->addr + entry->size, e820_type_to_string(entry));
+ }
+}
+
+/*
+ * How much should we pad the end of RAM, depending on where it is?
+ */
+static unsigned long __init ram_alignment(resource_size_t pos)
+{
+ unsigned long mb = pos >> 20;
+
+ /* To 64kB in the first megabyte */
+ if (!mb)
+ return 64*1024;
+
+ /* To 1MB in the first 16MB */
+ if (mb < 16)
+ return 1024*1024;
+
+ /* To 64MB for anything above that */
+ return 64*1024*1024;
+}
+
+#define MAX_RESOURCE_SIZE ((resource_size_t)-1)
+
+void __init e820__reserve_resources_late(void)
+{
+ int i;
+ struct resource *res;
+
+ res = e820_res;
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ if (!res->parent && res->end)
+ insert_resource_expand_to_fit(&iomem_resource, res);
+ res++;
+ }
+
+ /*
+ * Try to bump up RAM regions to reasonable boundaries, to
+ * avoid stolen RAM:
+ */
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+ u64 start, end;
+
+ if (entry->type != E820_TYPE_RAM)
+ continue;
+
+ start = entry->addr + entry->size;
+ end = round_up(start, ram_alignment(start)) - 1;
+ if (end > MAX_RESOURCE_SIZE)
+ end = MAX_RESOURCE_SIZE;
+ if (start >= end)
+ continue;
+
+ printk(KERN_DEBUG "e820: reserve RAM buffer [mem %#010llx-%#010llx]\n", start, end);
+ reserve_region_with_split(&iomem_resource, start, end, "RAM buffer");
+ }
+}
+
+/*
+ * Pass the firmware (bootloader) E820 map to the kernel and process it:
+ */
+char *__init e820__memory_setup_default(void)
+{
+ char *who = "BIOS-e820";
+
+ /*
+ * Try to copy the BIOS-supplied E820-map.
+ *
+ * Otherwise fake a memory map; one section from 0k->640k,
+ * the next section from 1mb->appropriate_mem_k
+ */
+ if (append_e820_table(boot_params.e820_table, boot_params.e820_entries) < 0) {
+ u64 mem_size;
+
+ /* Compare results from other methods and take the one that gives more RAM: */
+ if (boot_params.alt_mem_k < boot_params.screen_info.ext_mem_k) {
+ mem_size = boot_params.screen_info.ext_mem_k;
+ who = "BIOS-88";
+ } else {
+ mem_size = boot_params.alt_mem_k;
+ who = "BIOS-e801";
+ }
+
+ e820_table->nr_entries = 0;
+ e820__range_add(0, LOWMEMSIZE(), E820_TYPE_RAM);
+ e820__range_add(HIGH_MEMORY, mem_size << 10, E820_TYPE_RAM);
+ }
+
+ /* We just appended a lot of ranges, sanitize the table: */
+ e820__update_table(e820_table);
+
+ return who;
+}
+
+/*
+ * Calls e820__memory_setup_default() in essence to pick up the firmware/bootloader
+ * E820 map - with an optional platform quirk available for virtual platforms
+ * to override this method of boot environment processing:
+ */
+void __init e820__memory_setup(void)
+{
+ char *who;
+
+ /* This is a firmware interface ABI - make sure we don't break it: */
+ BUILD_BUG_ON(sizeof(struct boot_e820_entry) != 20);
+
+ who = x86_init.resources.memory_setup();
+
+ memcpy(e820_table_kexec, e820_table, sizeof(*e820_table_kexec));
+ memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
+
+ pr_info("BIOS-provided physical RAM map:\n");
+ e820__print_table(who);
+}
+
+void __init e820__memblock_setup(void)
+{
+ int i;
+ u64 end;
+
+ /*
+ * The bootstrap memblock region count maximum is 128 entries
+ * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries
+ * than that - so allow memblock resizing.
+ *
+ * This is safe, because this call happens pretty late during x86 setup,
+ * so we know about reserved memory regions already. (This is important
+ * so that memblock resizing does no stomp over reserved areas.)
+ */
+ memblock_allow_resize();
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ struct e820_entry *entry = &e820_table->entries[i];
+
+ end = entry->addr + entry->size;
+ if (end != (resource_size_t)end)
+ continue;
+
+ if (entry->type == E820_TYPE_SOFT_RESERVED)
+ memblock_reserve(entry->addr, entry->size);
+
+ if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
+ continue;
+
+ memblock_add(entry->addr, entry->size);
+ }
+
+ /* Throw away partial pages: */
+ memblock_trim_memory(PAGE_SIZE);
+
+ memblock_dump_all();
+}